The RAAM's Shadow Add-on for Gears of War 3 has 9 achievements worth 175 gamerscore.
Play 10 matches of Versus as a member of Zeta (Barrick, Tai, Minh, or Valera)(Standard or Casual).
Using the Hammer of Dawn Command Center, kill 50 Locust.
Complete "RAAM's Shadow" in Standard Campaign on any difficulty.
Using the Loader, kill 10 Locust.
As Mauler, kill 10 Gears by reflecting their bullets using your shield.
Complete "RAAM's Shadow" in 4 player co-op in either Arcade or Standard mode.
Complete "RAAM's Shadow" in Arcade Campaign on any difficulty.
As RAAM, kill 50 Gears using your Kryll.
As RAAM, execute Minh 10 times in Versus MP (Standard or Casual).